Posted on 12/15/2004 6:33:43 AM PST by SwinneySwitch
AUSTWELL - While two sets of twins wintering on islands associated with the Aransas National Wildlife Refuge does not set a record, it is rare. In fact, it's the first time in 40 years the refuge has hosted two sets in one winter.
Other new records have been set this winter. At latest count, 216 whooping cranes - including 33 chicks - have arrived to set new records for both the total number as well as the number of chicks. The record topples the one set last year of 194 birds.
Twins have made it to the refuge 12 years for a total of 19 pairs. This is the fifth winter when more that one pair has arrived, said Tom Stehn, whooping crane coordinator for U.S. Fish and Wildlife Service.
One reason for its rarity could be that from 1965 to 1996 second eggs were taken from nests to build a flock in captivity.
"In those years, many pairs had no chance to bring two chicks to Aransas. The all-time best twinning winter was 1958-59 when four sets made it to Aransas. That winter, out of the nine chicks arriving, eight were twins and one was single," Stehn said.
This, he said, demonstrates the potential for having twins when habitat conditions are ideal at the Wood Buffalo National Park nesting grounds in Canada.
In an aerial survey made in June, the Canadian Wildlife Service counted 20 sets of twins.
"By mid-August, only five sets of twins remained," Stehn said. "Only two of those five sets arrived safely at Aransas. Mortality of young whooping cranes is high."
He explained, "Collisions with power lines is the No. 1 source of mortality for fledged whooping cranes. Predators and disease take many of the young chicks in their first couple of weeks of life."
Of the two sets that have made the 2,400-mile flight from Canada to South Texas this year, little is known about the pair and the two that have set up housekeeping on Matagorda Island because the mother is not banded.
The female with twins that is claiming territorial rights on San Jose Island is banded and her history is documented. She hatched and was banded in 1987 and mated in 1991, a typical age for whooping cranes to start nesting. She had her first chick at the age of 8.
"This is typical of a new pairing. They normally may not produce chicks for one to two years until they get everything just right as parents, both in ensuring eggs are fertile and having parenting skills to raise young," Stehn explained.
"She successfully brought her second chick to Aransas in 1997. Then in 1999, her mate died and she did not nest that year. She resumed nesting in 2000, but did not have any chicks with her new mate until this year when they successfully brought the twins. I call this pair the 'North Pump Canal' pair for where they first set up a territory on the refuge on Sundown Bay. After the female got a new mate, the pair moved their winter territory over to San Jose Island."
He added, "Twinning is rare. Although whooping cranes normally hatch two eggs, unusually only one chick survives. Biologists theorize that by laying two eggs, this is nature's way of maximizing the chance of raising one chick. The older chick will actually peck at the smaller chick hundreds of times. The older chick not only could injure its smaller sibling, but also gets more food from the adults."
Stehn said the two new sets of twins in Texas this year are in locations "very difficult to access."
However, noted Rockport wildlife photographer Diane Loyd hopes to find a way to photograph them as she did last year when she caught the Lobstick Family, including twins, in action.
Named after the Lobstick Marshes in the Canadian refuge, Loyd dubbed the male Hoss, which at age 26 has the distinction of being the world's oldest whooping crane. Loyd named the female Lady.
The family arrived at the refuge in November 2003 and claimed exclusive territorial rights to as much as 400 acres, Loyd said.
"The male of the pair takes primary responsibility for defending the territory and also serves as the leader in making any moves within territories."
A moment captured on film shows the male warning of a potential threat or danger. If there were sound, his signal would be a trumpet-like sound that can be heard two miles away."The alert is typically a territorial dispute. He is saying, 'This is my family, my territory. Stay away!'"
In the photograph Loyd titled "Unison Call," the juvenile twins continue to graze and pay no attention to the parents' warning cries.
Loyd remembers seeing her first whooping crane as a child while on a boating trip with a large group of family members. After a bumpy ride over rough waters, the boat caravan came to "smooth, slick water. It was peaceful, heaven, and then all of a sudden we see this huge, huge stately white bird. We all had to stop and watch. It was incredible."
An adult whooping crane stands about 5 feet tall and has a wingspan of up to 7 1/2 feet. By the time the family is ready to migrate south, the chicks are normally as tall as adults.
Cranes mate for life unless one dies or is lost and then the survivor will re-mate, perhaps as quickly as in two days. In the wild, a crane's lifespan is believed to be from 20 to 30 years. A productive pair can produce as many as 10 chicks.
Loyd remembers when there were no birds.
"And look at how many we have now. That's what's really exciting. Around the world, the conservation effort to save the whooping crane stands above all other efforts."
Louise Popplewell is a reporter for the Advocate. Contact her at 361-552-2803 or lpopple@txcr.net.
Once again Mother Nature has chosen a species
to endure.
Whooping crane ping!
Careful, we have a lot of "gun nuts" on FR! LOL Just kidding guys. Please no hate mail. : )
BTTT!!!!!!!
Original recipe or extra-crispy?
I've never seen these birds.... Sometime I'm going to have to take a trip down that way and take a boat ride and maybe get a chance to see them... They must be something to see in flight........ 7 foot wing span... thanks for the ping
enviro-con ping!
Dulce Cumpean, a student at Port Lavaca's Travis Middle School, and Darrin Welchert, a biologist with the U.S. Fish and Wildlife Service, use a spotting scope and binoculars Monday to take a gander at snow geese, sandhill cranes, northern pintail ducks and other birds during a tour of the Aransas National Wildlife Refuge's Myrtle F. Whitmire preserve near Indianola. The tour, taken by 27 Port Lavaca students, was sponsored by the Fish and Wildlife Service, which manages the refuge, and the Guadalupe-Blanco River Trust, a group dedicated to resource conservation in the Guadalupe River Basin.
Aransas State Park is great. We were down there a few years ago and it was toward the end of there stay. We only saw a couple from a distance, but they are awesome!
"When a whooping crane wants to mate or bond with another whooper, its crown becomes bright red. The crane struts around in a high-stepping march and shows off its beautiful plumage. The crane tries to "invite" another bird with its body language. Ruffling its feathers, growling, stomping its feet, and tossing its head in various displays is the "come on." If another crane is interested, it will mimic the first crane's movements. Then the two will dance side by side. Eventually the two cranes will create a duet with a sequence of calls that lasts between 15 and 40 seconds. This duet is called a unison call. Its purpose is to release tensions and help the two birds bond. When whooping cranes prepare to mate, they leap, bow, run around, and throw sticks in the air. Cranes are famous for their dancing."
We used to see them from time to time up in Idaho. Gray's lake is another breeding area.
...tastes like Condor.
BTTT!!!!!!!
The Eastern flock summers in Wisconsin and winters in FL.
The new group follows an ultra light down each fall.
http://www.savingcranes.org/
Wonderful story. Gorgeous, majestic birds. May their success in breeding continue.
We saw the cranes last year, but stayed land bound there at the refuge. Maybe this year we'll take a boat tour to get a better view.
"They" tried to start up a second migratory flock by having sand hill cranes hatch out and raise the whoopers. The whooping cranes had an identity crisis and never could figure out who they were and did not mate. Don't know if they have all died out or not. Saw one or two of them with the sandhill cranes in the New Mexico refuge - where they winter over, in the late 80s.
The story of the ultralight guided birds from Wisconsin is quite interesting. The birds are usually quite solitary and typically migrate in family groups - probable no more than three or four, maybe sometimes with a bunch of the smaller sandhills. "They" train the birds to follow the ultralights as a flock and take the young ones to Florida and then leave them pretty much on their own. This year there was one whose flight feathers did not grow in right. I don't know what they did, but they must have plucked it and new feathers grew in. By that time it was too late to train for the ultralights. They dumped him out in Wisconsin near an older whooper. When the older one decided it was too cold to stay on in the north country, he and the young one left, but the older one flew about 50 miles further than the baby. By chance the young one landed near a second whooper. The episode was repeated the second day with the young one again landing short. The next part of the story was that the young one was spotted half way to Florida - apparently following some sandhill cranes.
I saw one on the farm in Nebraska 40-50 miles southwest of Linclon in the late 40s. It had stopped overnight in the flat area south of our farm place.
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